Patent · US Expired

Holographic scanner disc with different facet areas

US4415224A · kind A · utility

64Cited by
2References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 8, 1981
Grant dateNov 15, 1983
Priority date
Expiry dateJun 8, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B26/106
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A scan pattern for a bar code scanner is produced by the combination of a coherent light source, a rotating disc with holographic facets and an array of fixed, beam folding mirrors. Light reflected from a bar code label follows a retroreflective path to a photodetector within the scanner. To reduce variations in the amount of light collected through different facets, the areas of the facets are varied as a function of beam elevation and beam path length.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.